Numerous mechanical finishing means exist, in which various members are employed, said members and their mode of action being selected as a function of the desired purpose: teazles, napping rollers to give a plush appearance to a piece made of spun yarns of fibers, fulling machine to give volume to the wool, vibrating belt or other device for mechanically projecting the piece on an obstacle in order to improve dimensional stability, etc . . . In all these techniques, the mechanical members come into contact with the textile piece and, during such contact, modify the structure that said piece had either after weaving or knitting or possibly after the finished article has been made, most often by a relative displacement of the yarns constituting the piece, or of the discontinuous fibers or continuous filaments constituting said yarns. In the majority of cases, such contact of the mechanical members is accompanied by a certain degradation of the piece by the filaments or fibers breaking. Furthermore, such contact between the pieces and the mechanical member may cause wear of the member and therefore a progressive change in the result obtained.
Yarn producers have proposed yarns constituted by continuous filaments with adherent microfilaments, obtained by star- or lamellar spinning. The pieces obtained by weaving or knitting such yarns are then subjected to a treatment intended to individualize the microfilaments, so that said piece has the suppleness, the touch, the bulk corresponding to the unitary microfilaments.
Such individualization of the microfilaments is effected with the aid of suitable chemical treatments in which the matrix ensuring adhesion of the unitary microfilaments, or superficially the interlamellar surface is attacked. In particular, sodium hydroxide is used for such chemical treatments when the microfilaments are made of polyester.
Such chemical treatments present multiple drawbacks: it is difficult perfectly to monitor all the parameters to obtain a uniform treatment (duration of treatment, temperature, concentration of the bath); the piece thus treated loses weight due to its partial dissolution; the treatments are long and expensive.
In the following text, the general term "piece" will designate all presentations of the woven or knitted fabrics: fabric or knit leaving the loom and in the form of a web of large length, part cut out from such a web or finished article.
It is an object of the present invention to propose a simplified treatment of textile pieces which not only modifies the structure thereof without causing continuous filaments in the yarns constituting the piece or article treated to break, but also, the constituent yarns being continuous filaments with adherent microfilaments, effects individualization of said microfilaments.